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WASHINGTON, April 6 (Xinhua) -- A study led by researchers at the University of Michigan (U-M) showed in animal studies that new cancer drug compounds they developed shrank tumors, with few side effects.The study, done in two mouse models of human cancer, looked at two compounds designed to activate a protein that kills cancer cells. The protein, p53, is inactivated in a significant number of human cancers. In some cases, it is because another protein, MDM2, binds to p53 and blocks its tumor suppresser function. This allows the tumor to grow unchecked. The new compounds block MDM2 from binding to p53, consequently activating p53."For the first time, we showed that activation of p53 by our highly potent and optimized MDM2 inhibitors can achieve complete tumor regression in a mouse model of human cancer," says lead study author Shaomeng Wang, director of the Cancer Drug Discovery Program at the U-M Comprehensive Cancer Center.Wang presented the study Wednesday at the American Association for Cancer Research 102nd annual meeting.Many traditional cancer drugs also activate p53 but they do so by causing DNA damage in both tumor cells and normal cells, causing side effects. These new MDM2 inhibitors activate p53 while avoiding the DNA damage common with other drugs. In this study, which was done in collaboration with Ascenta Therapeutics and Sanonfi-Aventis, researchers showed that these new drugs shrank tumors without significant side effects.Because p53 is involved in all types of human cancer, the new drug has potential to be used in multiple types of cancer. Further, the researchers also identified certain markers in tumors that predict which ones will be particularly sensitive to the MDM2 inhibitor, which would allow physicians to target the drug only to patients most likely to benefit.

WASHINGTON, May 11 (Xinhua) -- Johns Hopkins University researchers have demonstrated that human liver cells derived from adult cells coaxed into an embryonic state can engraft and begin regenerating liver tissue in mice with chronic liver damage.The work, published Wednesday in the journal Science Translational Medicine, suggests that liver cells derived from so- called "induced-pluripotent stem cells (iPSCs)" could one day be used as an alternative to liver transplant in patients with serious liver diseases, bypassing long waiting lists for organs and concerns about immune system rejection of donated tissue."Our findings provide a foundation for producing functional liver cells for patients who suffer liver diseases and are in need of transplantation," says Yoon-Young Jang, assistant professor of oncology at the Johns Hopkins Kimmel Cancer Center. "iPSC-derived liver cells not only can be generated in large amounts, but also can be tailored to each patient, preventing immune-rejection problems associated with liver transplants from unmatched donors or embryonic stem cells." A microsopic view shows human embryonic stem cells in various stages of differentiation into liver cells in this photo taken at Stanford University and released by the California Institute for Regenerative Medicine, March 9, 2009iPSCs are made from adult cells that have been genetically reprogrammed to revert to an embryonic stem cell-like state, with the ability to transform into different cell types. Human iPSCs can be generated from various tissues, including skin, blood and liver cells.Although the liver can regenerate in the body, end-stage liver failure caused by diseases like cirrhosis and cancers eventually destroy the liver's regenerative ability, Jang says. Currently, the only option for those patients is to receive a liver organ or liver cell transplant, a supply problem given the severe shortage of donor liver tissue for transplantation. In addition, mature liver cells and adult liver stem cells are difficult to isolate or grow in the laboratory, she says. By contrast, iPSCs can be made from a tiny amount of many kinds of tissue; and the embryonic stem- like iPSCs can grow in laboratory cultures indefinitely.For the study, Jang and colleagues generated human iPSCs from a variety of adult human cells, including liver cells, fibroblasts ( connective tissue cells), bone marrow stem cells and skin cells. They found that though the iPSCs overall were molecularly similar to each other and to embryonic stem cells, they retained a distinct molecular "signature" inherited from the cell of origin.

MOSCOW, April 12 (Xinhua) -- Does life exist on other planets beyond the solar system? Are there any other planets like the Earth in our universe? And what does the universe look like?On questions related to outer space, human beings have never stopped observing and thinking.Yuri Gagarin, who made the first manned space flight on April 12, 1961, and orbited Earth for 108 minutes before safely landing, opened a window named "space" to humankind. The Soviet cosmonaut's journey continues to be an inspiration for the world to "conquer" space -- but now for more peaceful purposes.After the Cold War, cooperation on space exploration and scientific researches has turned to a more pragmatic way. More and more countries are realizing that space programs are closely linked with their people's lives than ever before.GAGARIN'S LEGACY INSPIRES PEACEFUL COOPERATION IN SPACEThe UN General Assembly adopted a resolution earlier this month that declares April 12 the International Day of Human Space Flight. The resolution has been supported by more than 60 countries."Man's space odyssey, the fruitful cooperation of many states in outer space would have been impossible without the very first step, Yuri Gagarin's flight," said Vitaly Churkin, Russia's permanent representative to the United Nations.However, the first human space flight was actually a result of competition between the East and the West at the height of the Cold War when the Berlin Wall was built.That competition gradually evolved, however, into a joint space project that has drawn more than 15 nations -- the International Space Station (ISS). Such a project would almost impossible to imagine before.The Mars-500 project in Moscow, aimed at testing the physical and psychological strains on humans during a 500-day journey to "Mars," is another good example of the international cooperation in scientific research. The experiment included six crew members from four countries, including Russia, China, France and Italy.Compared with the times of Gagarin, who died in a 1968 plane crash,mankind has changed its approach to space exploration, rendering it more pragmatic. That's according to cosmonaut Pavel Vinogradov, now a deputy head of the Space Flight Center in the Energy Rocket-Space Corporation."Early romanticism and space race have gone. Countries have been replaced by the business-oriented cooperation in the recent decade," Vinogradov told Xinhua.Experts said the scale and costs of space explorations require massive international cooperation."Space programs have been more money-thirsty even than military programs, so the nations seek closer cooperation," Vinogradov said, "and this pays off."STARDUST YIELDS TO PRAGMATISMUnlike 50 years ago, space technologies now are more closely linked to people and more directly affect their daily lives. Nowadays, one just cannot imagine life without satellite TV or GPS.Veteran cosmonaut Georgy Grechko said orbits have become construction sites rather than military facilities and the space industry itself has swiftly evolved into just another sector of the global economy.Echoing Grechko, Vinogradov said space also is a testing ground for many other sectors, including the bio-technological and pharmaceutical industries."What is just as important, outer space has turned into a platform for close, open, and fruitful international cooperation for the benefits of global, universal peace and development," Russian President Dmitry Medvedev has said.UN General Assembly President Joseph Deiss has said that the newly established International Day of Human Space Flight should serve as an opportunity to reflect on the importance of peaceful use of space to develop essential technologies and scientific breakthroughs."Space technology is used in matters diverse, such as the fight against climate change, against desertification, and against the loss of biodiversity," Deiss said. "The satellite images provided have given essential data when it comes to avoiding the risks of natural disasters."So far, mankind has never stopped making progress beyond the earth's boundaries and the progress itself has never stopped sparking people's imagination about what is possible through the peaceful use and exploration of outer space.What's more, humankind has never stopped the space dream."The task of the government is to inject into the people an ability to dream," said Igor Zadorin, a member of Russia's National Strategy Council.Here is interesting news: NASA's head Charles Bolden arrived in Russia on the eve of Gagarin's flight anniversary and was expected to discuss Russia-U.S. cooperation on a joint flight to Mars by a nuclear-powered spacecraft.What can we expect in the future?

WASHINGTON, May 2 (Xinhua) -- Rice originated in China, a team of U.S. genome researchers has concluded in a study tracing back thousands of years of evolutionary history through large-scale gene re-sequencing.Their findings, which appear Monday in the latest issue of the Proceedings of the National Academy of Sciences (PNAS), indicate that domesticated rice may have first appeared as far back as approximately 9,000 years ago in the Yangtze Valley of China. Previous research suggested domesticated rice may have two points of origin -- India as well as China.Asian rice, Oryza sativa, is one of world's oldest crop species. It is also a very diverse crop, with tens of thousands of varieties known throughout the world. Two major subspecies of rice -- japonica and indica -- represent most of the world's varieties. Sushi rice, for example, is a type of japonica, while most of the long-grain rice in risottos are indica.Because rice is so diverse, its origins have been the subject of scientific debate. One theory -- a single-origin model -- suggests that indica and japonica were domesticated once from the wild rice O. rufipogon.Another -- a multiple-origin model -- proposes that these two major rice types were domesticated separately and in different parts of Asia. The multiple-origin model has gained currency in recent years as biologists have observed significant genetic differences between indica and japonica, and several studies examining the evolutionary relationships among rice varieties supported more than domestication in both India and China.In the PNAS study, the researchers re-assessed the evolutionary history, or phylogeny, of domesticated rice using previously published datasets, some of which have been used to argue that indica and japonica rice have separate origins. Using more modern computer algorithms, however, the researchers concluded these two species have the same origin because they have a closer genetic relationship to each other than to any wild rice species found in either India or China.In addition, the study's authors examined the phylogeny of domesticated rice by re-sequencing 630 gene fragments on selected chromosomes from a diverse set of wild and domesticated rice varieties. Using new modeling techniques, which had previously been used to look at genomic data in human evolution, their results showed that the gene sequence data was more consistent with a single origin of rice.In the study, the investigators also used a "molecular clock" of rice genes to see when rice evolved. Depending on how the researchers calibrated their clock, they pinpointed the origin of rice at possibly 8,200 years ago, while japonica and indica split apart from each other about 3,900 years ago. The study's authors pointed out that these molecular dates were consistent with archaeological studies.Archaeologists have uncovered evidence in the last decade for rice domestication in the Yangtze Valley beginning approximately 8, 000 to 9,000 years ago while domestication of rice in the India's Ganges region was around about 4,000 years ago."As rice was brought in from China to India by traders and migrant farmers, it likely hybridized extensively with local wild rice," explained New York University biologist Michael Purugganan, one of the study's co-authors. "So domesticated rice that we may have once thought originated in India actually has its beginnings in China."

BEIJING, Jan. 28 (Xinhua) -- China will further its efforts to harness the Huaihe River over the next five to 10 years in a bid to support the economic development of the regions along the river.The decision was announced Friday in a statement released after an executive meeting of the State Council, China's Cabinet, which was presided over by Premier Wen Jiabao.The work will include upgrading dams and water gates in flood diversion programs and building more irrigation and water conservancy projects in low-lying lands along the Huaihe River, said the statement.Further, efforts will be made to guard against water pollution and help urban and rural residents in the Huaihe River regions have sufficient access to clean water, it said.Also, more flood control reservoirs will be constructed, while more residents will be relocated from flood diversion areas as well as flood land.The cabinet urged government departments to earmark more funds and enhance management and cooperation in implementing these measures.The 1,000-kilometer Huaihe River, the third longest water way in China, originates from Mount. Taibai, central Henan Province, and runs eastward between the Yangtze River and the Yellow River, the two largest rivers in the country. It cuts through Henan and east China's Anhui and Jiangsu provinces before entering the Yangtze River via the Hongze Lake.The flood-prone river has a drainage area of about 180,000 square kilometers.

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